Carpenter Bees
Carpenter Bee
Carpenter Bee Damage (center)
Photo by Jerry A Payne, Clemson University
Photo by Lamar Merck, The University of Georgia
Photos used with permission, courtesy of
www.insectimages.org
It's always interesting to get inquiries from people
about bees hovering around their decks, gutters or siding. Some are amazed
to find perfectly round 3/8" holes that look as if a vandal had done
damage.
This little "vandal" is a carpenter
bee. A carpenter bee looks similar to a bumble bee.
Here are the differences between the two:
Though carpenter bees are very large and intimidating,
unlike their wasp relatives (hornets and yellowjackets), they are not generally
aggressive. Though capable of stinging (females only), these insect don't
usual sting unless provoked. The males may hover around and intimidate
people as they pass.
Carpenter bees are very interesting in that they will
enter primarily unpainted softwoods such as pine and chew that nice, 3/8"
entry hole. After chewing a relatively short entrance, the bee will chew
another tunnel, several inches long at a
ninety degree angle to the opening. Here a female will lay eggs
starting from the back, working toward the gallery opening.
These bees
nest inside of the wood. There is one generation of these insects
annually with most of the activity in the Spring. These bees are known to
return to previously used galleries from year to year, although other bees can
make new galleries as well.
The most common sites for these intruders include
fascia board (often behind the gutters), deck railings, unpainted lawn
furniture, posts and unpainted playground equipment.
Carpenter Bee Management
Some people don't mind these insect that much. As
with other bees, they are beneficial as pollinators of flowers. However,
other people are not as happy to have carpenter bees around and seek ways to
eliminate them.
There are three ways of dealing with the problem:
exclusion, trapping and pesticides.
Exclusion is done by sealing and then painting the wood
surfaces well. A good enamel or polyurethane is probably most
durable and is least likely to be attacked again. The best solution, if
possible, is to wrap
exposed wood with aluminum flashing in areas such as the gutter fascia.
The second option, trapping, is done using a new product call
The Carpenter
Bee Chamber. It is a wood strip with predrilled holes in the
front or bottom and
grooves in back that guides bees into a strong adhesive that traps the bees out of sight.
There are two models, one for use along fascia and another for use on soffits.
Finally, the most effective type of pesticide application for existing,
active Carpenter Bee galleries is dust. Unlike liquid products which are
absorbed into the porous wood, surface, dust remains on top of the wood and
available for the insect to contact. Another big advantage of dust is that the application targets this pest
within the gallery with virtually no affect
on non target organisms such as people or their pets.
There are several such products on the
market for this problem. The best are non repellent products such as carbaryl (Sevin)
dust and boric acid dust. We sell Apicide,
a carbaryl dust product and Borid Turbo
(boric acid aerosol dust) for those wishing to treat the problem. Either of the two
products may be applied into the entrance of an active carpenter bee gallery.
Only a small amount is needed for each gallery opening. The Boric Turbo
product is recommended for vertical openings since it will adhere to those areas
rather than falling down as the Apicide might do in such situations.
For overall control, commercial applicators are best
equipped to apply insecticides as liquids in a
wettable powder formulation (a powder that suspends in water) that will repel
and kill carpenter bees. The active ingredient, cypermethrin, is
sold under the Demon WP and Cynoff WP trade names. This type of
application is helpful where there are a lot of Carpenter Bees hovering
around and targeting individual gallery opening is not practical. We do not offer
these restricted use products products for sale to the general public.
Talk to us
If we have not answered your questions about carpenter
bees or if you have any questions about any pest species that you have concerns about, please contact us. We will try to
answer your inquiry promptly. If you do not receive a reply, please let us
know by resubmitting your letter. We get a huge amount of unsolicited mail
and we may accidentally overlook your inquiry. You may write
to us by clicking here, send a fax to 845-356-2836 or by calling
us
toll free number during our regular business hours, 8 am to 4 pm ET,
weekdays at 800-433-1128.
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